METHOD FOR FORMING WIRING, SEMICONDUCTOR DEVICE, AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

A wiring which is formed using a conductive film containing copper and whose shape is controlled is provided. A transistor including an electrode which is formed in the same layer as the wiring is provided. Further, a semiconductor device including the transistor and the wiring is provided. A resist mask is formed over a second conductive film stacked over a first conductive film; part of the second conductive film and part of the first conductive film are removed with use of the resist mask as a mask so that the first conductive film has a taper angle greater than or equal to 15° and less than or equal to 45°; and the resist mask is removed. The first conductive film contains copper.